SSB ICOM- IC M802 GREAT TRANSMISSION / POOR RECEPTION

[Cadence]

Originally Posted by impi

Hi to all the good folks on CF!

We installed a new SSB HF MARINE IC-M802 Icom unii on our cat over a year ago now.
The unit apparently has a 'Super terrific transmission' - so we are told by nearby boats who hear boats far afield commenting on this ... but we hear little to nothing.

In Raiatea, we met a fella called Richard who told us the issue was our antennae which uses a shroud with isolators on it.

He installed a 'rope antennae' ... and yeah ... maybe ... we had ever so slightly better reception ... not much though, and we ONLY HEAR YACHTS in close proximity ... kinda like a super VHF.

Today in Fiji, some sailor told us there is a setting on the 'receiving end' of the Icom which he called a 'damper' and it is possible we have it set high which allows for better reception on nearby yachts as opposed to those further afield - short range reception - long range transmission.

He suggested we set this value down in order to receive better signal over longer distances - he was not sure of the code, but suggested that by holding and entering certain softkeys one can adjust the 'damper down' a bit. He is foreign language speaking to English, so perhaps the word 'damper' is not correct?

He refers to a shorter wave oscillation for nearer objects or a greater wave oscillation for further objects?

We have googled and searched books for this setting ... I am afraid I find no such thing

Am I missing something simple here?

Can anyone come up with some suggestions ... we have had a number of cruisers and 'experts' try all the usual stuff without success!

I think he was referring to squelch, in my part of the world with damper. ka4wja appears to made a good post ref. your radio.

[Jim Cate]

Originally Posted by Cadence

I think he was referring to squelch, in my part of the world with damper. ka4wja appears to made a good post ref. your radio.

Ahhh, come on... everyone knows that damper is bush bread made in a campfire.

Squelch is what your sea boots do when the cockpit fills with water.



These technical terms should not be used indiscriminately!

Jim

[W3GAC]

To the fellow boater with a question directed to be about a 706 shutdown issue... I could figure out how to respond just to you... the email kept bouncing back as undeliverable. Hopefully you will see it here.

I have several 706s (car, two boats) and never had a situation of a full shutdown. There is a well known issue that I struggled with of very low xmit output (but the rig LCD never showed any signs of dimming) that might be related to your issue. My 706 never actually shut-off requiring use of the on/off button. But maybe your situation is a more severe manifestation of this known/ what I found... bad in-line fuse holders.

I had very long frustrating bout of very low output power HF & VHF despite both antennas having good SWR and as I said, no LCD dimming sign of issues. This turned out to be caused by a warning I read years ago (and ignored) to get rid of/ upgrade the 706 in in-line fuse holders. Slightly dissimilar metals + high humid boat/ car environment cause connection resistance. While cleaning them with wire brush temporarily helped, within a week it was back to low power again. If you are still using the original long 3A3G fuse/ holders with clip contacts I'd think it would be good to swap them out for 'prong' type fuses that more aggressively self-wipe/ clean and fuse/ matting contact are metallurgically compatible. Automotive stores and marine stores have this type of fuses/ holders.

So while this/ low voltage may or may not be causing your issue it's worth changing them regardless and checking out your complete power source lines. back to the battery.

Some other rigs Yaesu 100D has had issues with cold solder joints on the final hybrids that require resoldering but never heard of 706 final issues.

If you are not using your face plate remotely and it's never been removed , it might be worth removing (side release and slide panel sideways) and wipe the delicate gold contacts with Kleenex (actually slightly abrasive). If these contacts developed moisture/ impurities over time it certainly could cause a shutdown, but I've never heard of 706 issues with it. But in remote operation of 706s via Remote Rig over the internet, the 706 does shut down when the internet path of the handshake between the panel and unit is interrupted. I've had my panels on/ off several times and this action/ most contacts, switches, breakers, fuses are designed to self wipe/ clean by contact surfaces moving against each other. Sitting stagnant longterm is usually not good.

I don't think your issue is SWR related, per se. I have more than once inadvertently xmitted without any antenna on my 706s and never had a shutdown. But strapping your GT-15 directly to the lower ground part of your insulated shroud could be coupling severe amounts of RF into your whole boat ground system and maybe back to your rig. High RF around a rig can causes many unpredicted issues. I think it's worth temporarily separating the GT-15 / from the grounded section and/ or temporarily connecting it to a 10-20' wire pulled up by your halyard to see if this changes your shutdown issue.

I'll ping around on your issue for other ideas/ maybe others have experience with 706 shutdown, but try these recommendations for now and let me know if it solves your issue. Bob, W3GAC




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[impi]

Fellow cruisers, we are overwhelmed with the effort put in here to help us find a resolve.

We are printing the posts off to have 'paper' in front of us as we test through all the possibilities.

The SSB was installed by an expert in Florida and he tested the system with some distant centre out of Florida and came back with an 8/10 for reception which he said was great given we were tied to a dock at a mates house. However, since we left for open water, we found we just could not get the same results. We are mostly at anchor far from other boats so generally are in much clearer positions than other cruisers on the net.

We have had a number of cruisers come on-board to try and assist us but they also end up with our result.

The wiring on the SSB does have the correct cabling and the tuner sits just under the deck close to the shroud (I hope that is not causing interference) but the location does make for a short run between the tuner and outside. On the outside it runs now as a rope antennae whereas it was a 'shroud antennae'.

Reading through these posts I have come to realise I should have asked the question a year ago ... we have not paid attention to a number of these issues and we will now start with the process of illumination.

What is interesting to us, is that when we turn the generator on, we get marginally better reception?

Thanks so far ... we will advise when we find the gremlin ... I am sure we are not the only ones struggling with this ...

Much appreciated

Brent